1. Field of the Invention
The invention pertains to an x-ray examination apparatus comprising an arrangement for remote-controlled position indication by placing a marker in a field of x-rays. The invention also relates to an arrangement for providing remote-controlled position indication on x-ray images suitable for use in such an x-ray examination apparatus.
2. Description of the Related Art
An x-ray examination apparatus of said kind is known from the German Patentschrifi DE 32 28 577.
For performing appropriate medical treatment on a basis of a diagnosis obtained by using an x-ray image, it is desirable that information on orientation and/or position of a patient during x-ray examination is recorded on x-ray film together with the x-ray image. This is achieved by imaging relevant markers, e.g. lead-letters, which are at option placed in the x-ray beam. In the x-ray examination apparatus as described in the cited reference, information on the position and the orientation of a patient during examination is provided on x-ray images by imaging lead-letters simultaneously with imaging the patient. In the x-ray examination apparatus according to the cited reference, a disc containing a plurality of different lead-letters, each of them corresponding to one of a plurality of patient positions and/or orientations, is rotatably attached to an x-ray shutter. Implicitly it is obvious, that the x-ray examination apparatus described in the cited reference, comprises an x-ray detector consisting of a film holder containing x-ray sensitive film-material. A relevant choice of letters to be imaged on x-ray images can be made by suitable rotation of the disc. The disc is driven by an arrangement of cables, pulleys, a winch and a motor; said arrangement being placed in an extension of the film holder along a longitudinal direction of the patient table. In the arrangement as described in the cited reference, the motor for driving the disc is positioned beneath the patient table, so that for accommodating space for incorporating the motor, the patient table must be positioned at a sufficiently large height above a floor on which the x-ray examination apparatus is installed.